help to contain the outbreak. David. Thank you. I want to bring in ABC's medical editor. Dr. Besser, first of all, these two Americans, what are their chances of survival here? In this outbreak, 60% of people died. 40%, their bodies fight it off and they survive. This is a troubling number. Is there any kind of treatment? There's no medicine that will fight the virus, no vaccine but they'll give you fluids and medicine for your fever. Those can help. These two Americans were on the frontlines. We have pictures of you suiting up there. You were telling me within 15 minutes you feel the massive heat. Yeah. It's very hard to wear that equipment for long periods of time. Usually you see health care workers get sick early in an outbreak before this kind of equipment. I talked to CDC. They're worried people getting sick this far into it. Maybe people making mistakes. A couple weeks ago you were telling me your biggest fear someone would get on a plane undetected and we reported tonight a man getting on a plane and then he dies. He had no symptoms when he got on and sick when he got off. Those people who were in direct contact with him are at risk. They are going to need to monitor them. To make sure they don't spread it around thinigeria.

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